Based on a pricing model by Fundstrat, the cost of mining BTC is $8,038. This should thus be the a support level where the miners will rather hodl their coins than to sell at a loss.
The next fundamental support level is $3,000 to $4,000, where the shit hits the fan and miners are actually forced to shutdown.
Given that BTC has a high level of correlation with altcoins, any price support for BTC will almost inevitably act as a price support for altcoins as well.
Keep calm and hodl on!
https://www.cryptoinfomag.com/2018/03/17/btc-may-be-hitting-an-price-support-level-soon/